JPH0813668B2 - Method for assembling a vehicle body floor portion having a honeycomb sandwich structure floor panel - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for assembling a vehicle body floor portion of an automobile, and in particular, a floor panel between a side sill and a center tunnel has an upper surface plate and a lower surface plate. The present invention relates to a method for assembling a vehicle body floor portion having a honeycomb sandwich structure in which a honeycomb core is sandwiched between the two.

(Prior Art) In general, a floor portion of an automobile is composed of a vehicle body strength member such as a side sill or a center tunnel extending in the front-rear direction of the vehicle body, a cross member extending in the left-right direction, and a floor panel installed therebetween. There is. In that case, the floor panel is often formed as an integral structural panel having a tunnel portion forming a center tunnel by press-molding one flat plate.

By the way, since the floor panel has a large area, surface vibration is likely to occur. Such surface vibration of the floor panel causes noise. Therefore, it is necessary to prevent the surface vibration from being generated due to the vehicle body vibration or the like particularly in the portion forming the floor surface of the vehicle interior. In addition, the floor panel is also required to play a major role in suppressing vibration of the entire floor and blocking noise transmitted to the passenger compartment. Therefore, the floor panel is
It must have sufficient rigidity. However, in the case where the floor panel is integrally formed with the center tunnel as described above, since the floor panel is formed by a single flat plate having a large area, sufficient rigidity cannot be secured.

Therefore, usually, the unevenness is formed on the floor panel portion or the reinforcing member is attached to increase the rigidity thereof. Further, a sound insulating material such as an insulator is attached to the floor panel portion to improve the sound insulating property.

However, if such a reinforcing member or sound insulating material is attached, the weight of the vehicle body will inevitably increase. Also,
It is desirable that the floor surface of the passenger compartment be as flat as possible. However, when the uneven portion is provided or the reinforcing member or the sound insulating material is attached as described above, the unevenness is generated on the floor surface.

Under such circumstances, it has been proposed to construct the floor panel with a honeycomb sandwich structure panel, as disclosed in Japanese Utility Model Laid-Open No. 57-133479. A panel having a honeycomb sandwich structure is formed by sandwiching a honeycomb core between an upper surface plate and a lower surface plate and joining them together. Such a honeycomb sandwich panel is lightweight, yet has extremely high rigidity, and is also excellent in vibration damping and sound insulation. Therefore, if such a honeycomb sandwich structure is adopted for the floor panel, it is possible to make the plane portion of the floor surface of the passenger compartment a large area.

(Problems to be Solved by the Invention) By the way, since a panel having a honeycomb sandwich structure has extremely high rigidity, press molding is almost impossible. Therefore, when the floor panel has a honeycomb sandwich structure, it is necessary to use only the floor panel as a honeycomb sandwich panel and separate it from the center tunnel.

However, doing so would require that the floor panel be bonded to the center tunnel as well as the side sill. Since a honeycomb sandwich panel has a honeycomb core having a large gap between an upper surface plate and a lower surface plate, it cannot be joined to other members by spot welding, bolting or the like as in the related art.
Therefore, if the honeycomb sandwich floor panel is to be joined to the side sill and the center tunnel in the vehicle body assembly line, it is necessary to drastically change the conventional vehicle body assembly line.

The present invention has been made in view of such a problem, and an object thereof is to allow a floor panel to have a honeycomb sandwich structure with almost no change in a conventional vehicle body assembly line. is there.

(Means for Solving the Problems) In order to achieve this object, in the present invention, the structural panel arranged between the left and right side sills is used as the lower surface plate in the honeycomb sandwich structure. That is, in the structural panel, recesses are formed in the flat portions provided on the left and right sides of the center tunnel.
On the other hand, a sub-honeycomb panel is formed by joining a flat plate-shaped upper surface plate to the upper surface of the honeycomb core and sticking a mel sheet to the lower surface of the honeycomb core on a line different from the vehicle body assembly line. The sub-honeycomb panel is installed on the concave portion of the structural panel in the vehicle body assembly line. Then, the mel sheet of the sub-honeycomb panel is heated and melted to bond the honeycomb core to the structural panel.

(Operation) By doing so, the honeycomb core and the upper surface plate are sequentially arranged on the concave portion of the structural panel, and they are bonded to each other. That is, that part
A honeycomb sandwich structure in which a honeycomb core is sandwiched and joined between an upper surface plate and a lower surface plate is formed.

Then, the structural panel is molded in the same manner as the conventional one, and similarly joined to the side sill or the like. Further, since the sub-honeycomb panel is assembled in a step different from the vehicle body assembly line, it is only necessary to add a step of loading the sub-honeycomb panel and installing it on the structural panel to the vehicle body assembly line.

Therefore, the floor panel can have a honeycomb sandwich structure in almost the same process as in the conventional vehicle body assembly line.

In that case, the flat portion of the structural panel to which the honeycomb core is joined needs to be flat, but if it is simply flat,
The rigidity is reduced, and the transportation and the assembly are complicated. Further, it is difficult to prevent the sub-honeycomb panel from being displaced, and when the mel sheet is in a molten state, the sub-honeycomb panel may move and may not be properly bonded. In the present invention, since the concave portion is formed in the flat portion as described above, sufficient rigidity is secured. Further, since the sub-honeycomb panel is housed in the concave portion, displacement of the sub-honeycomb panel is also prevented.

(Examples) Examples of the present invention will be described below with reference to the drawings.

First, a structure of a vehicle body floor portion having a honeycomb sandwich structure floor panel formed by the method of the present invention will be described. In the drawings, FIGS. 1 and 2 show an example of a vehicle body floor structure, FIG. 1 is an exploded perspective view partially showing the vehicle body floor portion, and FIG. 2 is a vehicle body of the vehicle body floor portion. It is a vertical cross-sectional view in the left-right direction.

As is clear from these figures, a pair of side sills 1, 1 extending in the front-rear direction are provided on both left and right sides of the vehicle body floor at a position corresponding to the vehicle compartment floor surface. The side sill 1 is composed of a side sill outer panel 2 and a side sill inner panel 3 and has a hollow closed cross section.

Further, a pair of center frames 4, 4 extending in the front-rear direction is provided at the center of the vehicle body between the left and right side sills 1, 1. The center frame 4 has a channel shape that opens upward.

The side sills 1, 1 and the center frames 4, 4 are joined to each other by cross members (not shown) at front and rear ends thereof, thereby forming a skeleton of the vehicle body floor portion.

Between the left and right side sills 1, 1, there is a channel-shaped tunnel portion 5 that opens downward in the central portion, and flat portions 6, 6 extending from the tunnel portion 5 to the left and right sides.
A large structural panel 7 having is arranged. The structural panel 7 is formed by press-molding a single flat plate like the structural panel in the conventional vehicle body structure. The tunnel portion 5 of the structural panel 7 includes a pair of center frames 4,
Framed over them arranged over 4
By being joined to the upper ends of 4 and 4, a center tunnel 8 having a reinforcing portion having a hollow closed cross section is formed. Further, flanges 9 and 9 projecting upward are provided on both left and right edges of the structural panel 7, and the flanges 9 are joined to the side walls 3a of the side sill inner panel 3.

Thus, the structural panel 7 and the side sills 1, 1 and the like that form the frame of the vehicle body constitute a vehicle body floor structure.

The flat portion 6 of the structural panel 7 is provided with a relatively shallow recess 10 having a large area. A bottom plate 11 forming the bottom surface of the recess 10 is substantially flat.

On the other hand, the top plate 12 is formed by one flat plate that is thinner than the structural panel 7. Then, a honeycomb core 13 made of paper or the like is joined to the lower surface of the upper surface plate 12 while leaving the outer peripheral edge portion thereof, and further, a mel sheet 14 is attached to the lower end of the honeycomb core 13 to form a sub-honeycomb panel.
15 are formed. The upper surface plate 12 is sized so as to completely cover the recessed portion 10 and the outer peripheral edge portion thereof to be superposed on the stepped upper surface of the outer periphery of the recessed portion 10. Also, the honeycomb core 13
Is sized to be completely housed within the recess 10.

The sub-honeycomb panel 15 is installed on the bottom plate 11 of the recess 10 so that the honeycomb core 13 is housed in the recess 10, and is bonded to the bottom plate 11 by the mel sheet 14.

In this way, the floor panel 16 between the center tunnel 8 and the side sills 1, 1 is formed into a honeycomb sandwich structure in which the honeycomb core 13 is sandwiched and joined between the upper surface plate 12 and the flat portion 6 of the structural panel 7. . That is, in this floor panel 16, the flat plate 6 of the structural panel 7, particularly the bottom plate of the recessed portion 10 thereof, serves as the lower surface plate 17 constituting the honeycomb sandwich structure.

Next, a procedure for forming a vehicle body floor portion having the floor panel 16 having such a honeycomb sandwich structure will be described.

First, on a line different from the vehicle body assembly line, the upper surface plate 12 is bonded to one end surface of the honeycomb core 13 formed in a predetermined shape with an adhesive. And that honeycomb core 13
Attach the mel sheet 14 to the other end surface of the. Since the mel sheet 14 is in the form of an adhesive sheet, it can be easily attached to the end surface of the honeycomb core 13 only by pressing the honeycomb core 13. Thus, the sub-honeycomb panel 15 having a predetermined shape is formed.

In this way, by forming the sub-honeycomb panel 15 in a process different from the vehicle body assembly line, the assembly process of the sub-honeycomb panel 15 does not affect each process of the vehicle body assembly line. Adhesion between the honeycomb core 13 and the upper surface plate 12 can take a sufficient time, and the adhesion can be made reliable and strong.

On the other hand, in the vehicle body assembly line, as in the conventional case, the vehicle body strength members such as the side sills 1, 1 and the center frames 4, 4 are combined to form the skeleton of the vehicle body floor portion. Further, similarly to the conventional floor panel, by pressing one steel plate, the structural panel 7 having the flat portions 6, 6 on both sides of the tunnel portion 5 is formed. At that time, a concave portion 10 is simultaneously formed in the flat portion 6. Then, the structural panel 7 is joined to the side sills 1, 1 and the center frames 4, 4, etc. In this case, since the concave portion 10 is formed in the flat portion 6 of the structural panel 7, the flat portion 6 is given a considerable rigidity due to the shape effect. Therefore, even if the flat panel 6 has a large area, the structural panel 7 can be easily transported and assembled.

Next, the sub-honeycomb panel 15 previously formed as described above is carried into the vehicle body assembly line.
The loading may be performed before the structural panels 7 are joined, but it is desirable that the washing is completed in the vehicle body painting process. That way,
Even when the honeycomb core 13 is made of paper, it is prevented that the honeycomb core 13 is wet and broken by the cleaning water.

In the car body assembly line, its sub-honeycomb panel
As shown in FIG. 2, the honeycomb core 13 is housed in the recessed portion 10 of the structural panel 7, and the mel sheet 14 is in contact with the bottom plate 11 of the recessed portion 15, so that the bottom plate 17 is provided. Set to. Then, a weight is placed on the top plate 12 to press it from above. In that case, it is desirable to apply a sealing material such as a sealer to the lower surface of the outer peripheral edge of the upper surface plate 12. By doing so, the upper surface plate 12 is bonded to the upper surface of the outer peripheral step portion of the recessed portion 10 of the lower surface plate 17, and the inside of the recessed portion 10 is completely sealed.

In that state, the mel sheet 14 is heated. If the sub-honeycomb panel 15 is assembled after the completion of washing with water in the coating process as described above, the vehicle body is then dried in the coating process, so the mel sheet 14 is heated by the heat during the drying. Therefore, by doing so, it is possible to eliminate the special equipment and process for heating the mel sheet 14.

The mel sheet 14 is used as a vibration damping material, but since it contains asphalt as a main component, it melts when heated. Therefore, even if the bottom plate 11 of the recessed portion 10 is slightly distorted, the bottom plate 11 surely adheres to the bottom plate 11. Also, since the mel sheet 14 has a considerable thickness, the honeycomb core 13
The cell wall end of the plunge into the mel sheet 14. Particularly when the honeycomb core 13 is made of paper, the melted mel sheet penetrates into the cell walls of the honeycomb core 13. As a result, when the mel sheet 14 is cooled and hardened, the mel sheet 14 reliably and firmly bonds the honeycomb core 13 and the bottom plate 11 of the recessed portion 10.

In the meantime, the sub-honeycomb panel 15 is relatively flexible because the thin upper surface plate 12 is bonded to only one surface of the honeycomb core 13. Therefore, the recess
Even if the bottom plate 11 of 10 is slightly distorted, it can be easily aligned with it. Further, even if the bottom plate 11 has small irregularities, it is absorbed by the mel sheet 14. Therefore, regardless of the processing error and the assembly error of the structure panel 7,
The honeycomb core 13 is uniformly adhered to the lower surface plate 17 which is a part of the structural panel 7 over the entire surface.

Further, since the honeycomb core 13 is housed in the recessed portion 10, the sub-honeycomb panel 15 is prevented from being displaced with respect to the structural panel 7. Therefore, even when the mel sheet 14 is in a molten state, the honeycomb core 13 is held in a fixed position, and the bonding is properly performed.

In this way, the sub-honeycomb panel 15 is joined to the structural panel 7. And at that time, side sill 1
A floor panel 16 having a honeycomb sandwich structure integral with the center tunnel 8 is formed between the center tunnel 8 and the center tunnel 8. Therefore, the floor panel 16 having such a honeycomb sandwich structure can be manufactured only by adding a step of loading and setting the previously formed sub-honeycomb panel 15 to the conventional vehicle body assembly line.
That is, the conventional vehicle body assembly line can be used almost as it is.

Moreover, in the car body assembly line
Since it is only necessary to carry in the sub-honeycomb panel 15 that is pasted up to 14 and made into one component, the man-hours are reduced and the component management becomes easy as compared with the case where the mel sheet 14 is separately carried in. Moreover, since the rigidity of the sub-honeycomb panel 15 is increased by sticking the mel sheet 14, it is easy to carry in and assemble the sub-honeycomb panel 15.

In the honeycomb sandwich structure floor panel 16 formed in this manner, since the mel sheet 14 as a vibration damping material is interposed between the lower surface plate 17 and the honeycomb core 13, such a floor panel By setting it to 16, minute vibrations transmitted from the engine etc. will be effectively absorbed.

FIG. 3 shows another embodiment of the vehicle body floor portion structure formed by the method of the present invention.

As is clear from this figure, the structural panel 7 in this case
Also, similarly to the above-mentioned embodiment, the tunnel portion 5 and the flat portion 6 are integrally formed. The edge 6a of the flat portion 6 on the side sill 1 side is a side wall of the side sill interpanel 3.
The flange 9 is formed by being bent upward along 3a. Then, the flange 9 and the side wall 3a are joined by welding. In addition, the center tunnel 8 of the flat portion 6
The side edge portion 6b is common to the side wall 5a of the tunnel portion 5. In this way, both side edge portions 6a, 6b of the flat portion 6 are bent upward, so that the recessed portion 10 is formed in the entire flat portion 6.

Even when such a structural panel 7 is used, the sub-honeycomb panel 15 formed by joining the honeycomb core 13 and the upper surface plate 12 in advance and attaching the mel sheet 14 to the lower end portion of the honeycomb core 13 has the concave portion. Honeycomb core in part 10
13 is set and set on the flat portion 6. In that case, both side edge portions of the top plate 12 are also bent upward, and are joined to both side edge portions 6a, 6b of the flat portion 6 by the both side edge portions.

The mel sheet 14 attached to the sub-honeycomb panel 15 is heated by the drying heat or the like at the time of drying the vehicle body in the coating process, as in the above-described embodiment, whereby the honeycomb core 13 and the bottom plate 11 of the recess 10 are formed. Are glued together. Thus, the honeycomb sandwich structure floor panel 16 is formed between the side sill 1 and the center tunnel 8. Also in that case, the flat portion 6 of the structural panel 7 becomes the lower surface plate 17 constituting the honeycomb sandwich structure.

Even when forming such a floor panel 16, there is almost no need to change the conventional vehicle body assembly line. Further, since the lower surface of the vehicle body floor portion is substantially flat, it can be easily supported.

(Effects of the Invention) As is apparent from the above description, according to the present invention, a concave portion is provided in a flat portion of a structural panel molded in the same manner as a conventional floor panel, and the upper surface plate is previously formed in the concave portion. Since the honeycomb core attached with the mel sheet and the mel sheet is set and the mel sheet is heated and melted, the floor panel portion between the side sill and the center tunnel is honeycomb-sandwiched in almost the same process as the conventional car body assembly line. Can be formed into a structure. Moreover, since the honeycomb core is carried into the vehicle body assembly line as a sub-honeycomb panel in which the upper surface plate is joined to the upper end and the mel sheet is stuck to the lower end, the carrying-in and assembling are as follows.
The conventional mel-sheet attaching process can be used as it is. Further, if the mel sheet is heated by using the heat of drying the vehicle body in the painting process, it is not necessary to newly install it. Therefore, it is possible to form a vehicle body floor portion having a floor panel having a honeycomb sandwich structure with almost no change in the conventional vehicle body assembly line.

Further, since the concave portion is formed in the flat portion of the structural panel, the rigidity of the flat portion is high even though the flat portion has a large area. Therefore, the structural panel hardly bends even during transportation, and when the structural panel is set on a jig or the like in the welding process or the like, it can be accurately and easily performed.
In addition, since the honeycomb core is positioned by the recessed portion, the honeycomb core is not displaced during bonding to the structural panel, and reliable bonding can be achieved at an accurate position. Furthermore, by using a mel sheet for the adhesion, even if there is some distortion in the structural panel,
Since the mel sheet comes into close contact with the bottom surface of the recessed portion of the structural panel and absorbs the strain, the honeycomb core can be evenly adhered over the entire surface.

[Brief description of drawings]

FIG. 1 is an exploded perspective view partially showing an example of a vehicle body floor portion formed by the method of the present invention, FIG. 2 is a vertical sectional view of the vehicle body floor portion in the vehicle body left-right direction, and FIG. FIG. 5 is a vertical sectional view similar to FIG. 2, showing another example of the vehicle body floor portion formed by the method of the present invention. 1 ... Side sill, 5 ... Tunnel part, 6 ... Flat part 7 ... Structural panel, 8 ... Center tunnel, 10 ... Recessed part 12 ... Top plate, 13 ... Honeycomb core, 14 ... Mel sheet 15 …… Sub-honeycomb panel, 16 …… Floor panel 17 …… Bottom plate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-1-119483 (JP, A) JP-A-1-119482 (JP, A) JP-A-1-119484 (JP, A) Jikkenhei 6- 11903 (JP, Y2) Actual Public Flat 5-32388 (JP, Y2) Actual Public Flat 6-11904 (JP, Y2)

Claims (1)

[Claims] 1. A tunnel portion forming a center tunnel is integrally molded in a central portion, and a concave portion is formed in a flat portion provided on both left and right sides of the tunnel portion of a structural panel arranged between left and right side sills. In advance, a flat top plate is joined to the upper surface of the honeycomb core in advance, and a sub-honeycomb panel formed by attaching a mel sheet to the lower surface of the honeycomb core is placed on the concave portion of the structural panel in the vehicle body assembly line. Installed in
A method for assembling a vehicle body floor portion having a floor panel having a honeycomb sandwich structure, characterized in that the honeycomb core is adhered to a structural panel by heating and melting the mel sheet.